To obtain a compsn. which acts as a viscosity modifier and a dispersant for lubricating oils and fuels by incorporating a hydrocarbon polymer having specific pendant groups bonded thereto and a specified mol.wt. into the same.
This compsn. contains a hydrocarbon polymer which, when it is not a star polymer, has an Mn of 20,000 to about 500,000 and when it is a star polymer, has a GPC peak mol.wt. of up to about 4,000,000 and which has pendant groups Aa and Bb bonded thereto. Here, A is a group of formula A:-Q-Kk, and B is a group of the formula. In formula A, Q is an aliph. or arom. hydrocarbon group; K is amido. CN, ester, or COOH; k is 1 to about 4 provided when k≥2, then two K groups on adjacent carbon atoms may combine with each other to form an imide group; and suffix a is 0 to about 50. In the formula, X is 0, S, or NRb; Rb is B, NH2, or the like; s is 1 or 2; Z is hydrocarbyl; Ra is ethylene or propylene; and suffix b is 1 to about 40 provided that when X is 0, then b is 2 to about 40.
LANGE RICHARD M
VARGO DANIEL M
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